The Statistics and Data Management Core will provide essential support for statistical analysis and data management for the three projects proposed in this application. For the past 25 years, the Biostatistics Unit at the Feinstein Institute for Medical Research has collaborated with investigators at the NSLIJ Health System and other Institutes in Phase I,II and III trials that are sponsored by NIH or by pharmaceutical companies. Dr. Martin Lesser, the Core Learder and the Director of the Biostatistics Unit, and other Core members have extensive experience in the design, data management, and analysis of clinical research projects/trials. This core consists of two components. The Biostatistics component will support Project teams of all three Projects by providing statistical advice in study design, data analysis and interpretation. Additionally, for the Project 3, the Core will explore new methods of statistical classification for differential diagnosis of patients with parkinsonism. The other component of the Core is Data Management, which will have primary responsibility for the development and maintenance of the data management system and procedures for all the projects in this application. Support will be provided in many areas including case report form development, data entry, database programming, database query, data quality assurance, report production, auditing, etc.